In the stiffening of selected areas of shoe uppers, particularly the toe and heel ends for the purpose of preserving a desired shape, a well accepted method is that forming the subject matter of the U.S. Pat. No. 3,316,573 to Chaplick and Rossitto, dated May 2, 1967 in which molten resin is applied as a thin layer to the portion to be stiffened and is cooled to stiff, resilient condition. When the shoe includes a lining, the lining may be pressed against the resin while the resin is still tacky and adhesive to bond the lining in place in the shoe.
Shoes of which portions have been stiffened by the process of the patent have been found very satisfactory for most purposes. However, particularly for men's shoes, and in shoe counters, greater stiffness and strength are sometimes desirable. This need cannot be met by simply using a thicker layer of resin because of difficulties of maintaining interior smoothness because of bubbles entrapped in the resin as well as difficulties in shoemaking and in breakdown in the finished shoe.